Even after he’d risen to fame — when, in Ireland, bells rang and bonfires burned to celebrate his birthday each year — Jonathan Swift sent much of his writing into the world without signing his name to it.

It wasn’t humility that kept him in the shadows. Swift (1667-1745) had an ego of such staggering sensitivity that a perceived slight could land a person on his enemies list for a lifetime. He did relish the success of a good covert operation, but that wasn’t his reason for authorial secrecy. Nor was it necessarily fear for his job, though he was an Anglican priest and, for his last three decades, dean of St. Patrick’s Cathedral in Dublin.

Mostly, in an era when English law regarded freedom of speech as something to be actively discouraged — with, say, imprisonment — he was trying to avoid prosecution. Even when a piece of writing was commonly assumed to have come from his pen, and it often was, he was careful to preserve deniability.

There is some irony, then, in wishing that Leo Damrosch’s tremendous new biography, “Jonathan Swift: His Life and His World,” had been more reticent about displaying Swift on its cover. There is nothing like an oil portrait of a bewigged 18th-century white man to telegraph that the contents of a book, particularly one published by a university press, must be dreary, dutiful reading.

JONATHAN SWIFT: His Life and His World

Author:

Leo Damrosch

Publisher:

Yale University

Number of pages:

592 pp.

Book price:

$35

But “Jonathan Swift” is a lively and pleasurable experience: vigorous, compassionate, occasionally pugnacious, sometimes laugh-out-loud funny — and not just because Damrosch, who is Ernest Bernbaum professor of literature at Harvard, knows how to pluck and present a vivid quotation. He also has a gift for dry one-liners, and the invaluable ability to write about humor and wit without choking the air out of them.

“When I am reading a book, whether wise or silly . . . it seemeth to me to be alive and talking to me,” Swift wrote. That’s true of good books, anyway; it’s true here.

Swift was English and Irish; Tory and Whig; preacher, poet, political player. Irish-born, he longed for London, thrived there for a time, and never got over his failure to remain in England. Even as he became a hero to the country of his birth, he bemoaned having to live in “wretched Dublin in miserable Ireland.”

Damrosch sifts three centuries of history, biography, and literary criticism to arrive at an evaluation of Swift that explicitly builds on and wrangles with the verdicts of his predecessors. Irvin Ehrenpreis, author of the three-volume biography “Swift: The Man, His Works, and the Age” (1962-83), comes in for some takedowns, particularly on sexual matters, that are Swiftian in their aggressiveness.

But Damrosch does not affect omniscience. A National Book Award finalist for his 2005 biography “Jean-Jacques Rousseau: Restless Genius,” he is straightforward about the difficulty of getting a firm hold of Swift, given “the slipperiness of most evidence” about his life and the utter absence of evidence about significant parts of it.

The whole he makes of those fragments is a complex and tantalizing portrait of ambition, intrigue, oppression, art, and exile. Savvily, he leads with sex.

What was going on between Swift and Stella, his closest friend, whom he’d known since he was 22 and she was 9? Were they lovers? Were they secretly married? Were they — small complicating detail — uncle and niece?

And what of Vanessa, the beautiful, much younger woman who followed Swift from England to Ireland when he was middle aged?

A capacity for empathy and imagination pervades the book, shaping not only the way Damrosch views his subjects but also the Swiftian clarity with which he writes.

Swift was a passionate reader, given to marginalia. “Bloody inhuman hell-hound of a king,” he seethed in the margins of a Henry VIII biography — one of his less violent reactions to that book.

Swift got grumpier and grumpier as he aged. Reading “Jonathan Swift” with pencil in hand, there is a temptation to urge him, in the margins of the later pages, to get a grip.

Damrosch’s book, and the centuries-old voices in it, are alive and talking to us. How could we not talk back?